JDBC- Statement example - Execute CREATE table query(DDL command) using Statement's executeUpdate method in java


In this tutorial we will learn how to Execute CREATE table query(DDL command) using java.sql.Statement's executeUpdate method in java JDBC.



What is Statement in JDBC (java database connectivity)?

  1. The java.sql.Statement object used for executing a static SQL statement and returning the results it produces.

  1. Statement cannot accept parameters at runtime in java JDBC.

  1. Statement is slower as compared to PreparedStatement in java JDBC.

  1. Statement is suitable for executing DDL commands - CREATE, drop, alter and truncate in java JDBC.
  2. Statement can’t be used for storing/retrieving image and file in database (i.e. using BLOB, CLOB datatypes) in java JDBC.
  3. Statement enforces SQL injection, because we end up using query formed using concatenated SQL strings in java JDBC.
Statement Example in java JDBC >
stmt = con.createStatement();
stmt.executeUpdate("DELETE from EMPLOYEE where ID=2 ");

  1. same SQL query can’t be executed repeatedly in Statement .
  2. Statement  makes code less readable and understandable - We may need to write concatenated SQL strings
  3. java.sql.Statement is an interface in java JDBC.

  1. By default, only one ResultSet object per Statement object is allowed to be opened at the same time in java JDBC.

  1. java.sql.Statement Important methods in java JDBC -




java.sql.Statement's executeUpdate method can be used for executing CREATE table queries  in java JDBC.


--Before executing java program execute these database scripts  >
None

--If table already exists then execute the DROP command >
drop table EMPLOYEE;

If table already exist and below program is executed then you will face error in creating table (ORA-00955: name is already used by an existing object)


Must read : java.sql.Statement - using executeUpdate  and executeQuery methods SELECT,INSERT, UPDATE, DELETE


Example/ Full Programs JDBC- Execute CREATE table query using Statement's executeUpdate method in java
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.sql.Statement;
/** Copyright (c), AnkitMittal JavaMadeSoEasy.com */
public class StatementCreateExample {
   public static void main(String... arg) {
          Connection con = null;
          Statement stmt = null;
          try {
                 // registering Oracle driver class
                 Class.forName("oracle.jdbc.driver.OracleDriver");
                 // getting connection
                 con = DriverManager.getConnection(
                              "jdbc:oracle:thin:@localhost:1521:orcl",
                              "ankit", "Oracle123");
                 System.out.println("Connection established successfully!");
                
                 stmt = con.createStatement();
                 //execute create table query
                 stmt.executeUpdate("create table EMPLOYEE("
                                                    + "ID number(4), NAME varchar2(22))");

                 System.out.println("EMPLOYEE Table created");
          } catch (ClassNotFoundException e) {
                 e.printStackTrace();
          } catch (SQLException e) {
                 e.printStackTrace();
          }
          finally{
                 try {
                       if(stmt!=null) stmt.close(); //close Statement
                       if(con!=null) con.close(); // close connection
                 } catch (SQLException e) {
                       e.printStackTrace();
                 }
          }
   }
}
/*OUTPUT
Connection established successfully!
EMPLOYEE Table created
*/



So, in this tutorial we learned how to Execute CREATE table query(DDL command) using Statement's executeUpdate method in java JDBC.


RELATED LINKS>

Oracle 11g and SQL Developer installation and setup on 32/64bit windows - explained step by step with screenshots


java.sql.PreparedStatement - using executeUpdate  and executeQuery methods - CREATE, SELECT, INSERT, UPDATE and DELETE

JDBC- Insert/Store/save FILE in database

JDBC- Batch PreparedStatement example- Execute INSERT query(DML command) using PreparedStatement's addBatch() and executeBatch() methods in java


Execute database STORED PROCEDURE - IN parameter, OUT parameter and IN OUT parameter || call FUNCTION from java

Difference between CLOB and CLOB data type in Oracle


No comments:

Post a Comment